Re: [PATCH] seq: speed up the common case by 25x

[Pádraig Brady]

On 01/04/11 10:20, Jim Meyering wrote:
> Pádraig Brady wrote:
>>     seq: speed up the common case by 560%
>>
>>     * seq.c (print_range): Print a range of numbers
>>     without using if statements for speed.
>>     (print_long_range): Print a range of numbers
>>     using the unix paradigm of using other utils
>>     that do it better.
> 
> Great idea.

> I get this:
> 
>   $ env time ./seq 10000000 > /dev/null
>   0.50user 0.06system 0:00.20elapsed 273%CPU (0avgtext+0avgdata 
> 4800maxresident)k
>   ...
> 
> Compare with the old version's time:
> 
>   5.06user 0.00system 0:05.08elapsed 99%CPU (0avgtext+0avgdata 
> 2608maxresident)k
> 
> So here I benefit from parallelism, and end up with not just 560% (5.6x)
> but a 25x(!) speed-up (on an i7-970).

My April fool's joke has spectacularly backfired.